Impact Energy Absorption Control of Metal 3D Printed Meta-Structures through Beam-Based Unit Cell Design
- 주제(키워드) Additive Manufacturing , AlSi10Mg , Crashworthiness , Meta-Structure , TPMS , High-Energy Impact , Volumetric Design , Hybrid Lattice
- 발행기관 서강대학교 일반대학원
- 지도교수 김동철
- 발행년도 2026
- 학위수여년월 2026. 2
- 학위명 석사
- 학과 및 전공 일반대학원 기계공학과
- 실제URI http://www.dcollection.net/handler/sogang/000000082737
- UCI I804:11029-000000082737
- 본문언어 영어
- 저작권 논문은 저작권에 의해 보호받습니다.
초록(요약문)
Meta-structures can provide impact absorption behaviors that are difficult to achieve with conventional collision members. Additive manufacturing further expands the usable design space by enabling complex lattice geometries. However, most impact-absorption studies using meta-structures have been conducted under low-impact energies (typically < 1 kJ). In practical vehicle front structures, at least ~1 kJ must be absorbed, and the absorbed energy can reach the order of ~25 kJ depending on the crash scenario. This gap motivates high-impact-energy design and validation at the unit-cell and component levels. This study targets high impact energies of 1–10 kJ and aims to control the force–displacement response under such conditions. A PBF (powder bed fusion) process with AlSi10Mg is adopted, and a stress-state dependent ductile damage model is developed to predict fracture during impact. The damage model is calibrated using tensile specimen sets designed to cover multiple stress states (e.g., uniaxial tension, shear-dominated, and plane-stress-dominated conditions). The model form follows an incremental stress-state dependent approach (GISSMO) with a Hosford–Coulomb failure locus to reduce prediction errors under changing stress states during impact. Based on triply periodic minimal surface (TPMS)-derived base morphologies, a beam-based unit cell design is proposed. The load-transfer and deformation mechanisms are interpreted through beam orientation and stress/strain state evolution. High-energy impact simulations are performed to compare candidate unit cells and to refine designs that lower peak force and suppress excessive densification while maintaining stable deformation. Design variables such as unit cell shape, volume fraction, and aspect ratio are then organized into impact energy– driven design relationships to support target-performance selection. Component-level performance is finally demonstrated by comparing the proposed meta-structure absorber against a reference crash box under equivalent impact conditions, showing improved energy absorption efficiency and reduced peak force/displacement. In summary, the novelty of this work is the demonstration and controllability of force– displacement performance in a high-impact-energy regime (1–10 kJ) using AM AlSi10Mg meta-structures. The study connects (i) a validated stress-state dependent damage model, (ii) TPMS-derived beam-wise unit cell design, and (iii) impact-energy-based design guidelines to enable practical collision members that can be tuned to a target peak force or maximum displacement at high energies. Keywords: Additive Manufacturing, AlSi10Mg, Crashworthiness, Meta-Structure, TPMS, High-Energy Impact, Volumetric Design, Hybrid Lattice
more목차
1. Introduction 9
2. Damage modeling for additively manufactured (AM) aluminum alloy 12
2.1. Tensile Specimen Design based on triaxiality and mesh size
2.2. Calibration and validation of AM aluminum alloy damage model
3. TPMS-Derived meta structure unit cell development for high energy impact absorption 20
3.1. TPMS-Based Unit Cell Generation and Structural Categorization
3.2. High-Energy impact evaluation and optimization of unit cells
4. Impact energy-Driven structural design guideline 32
4.1. Design strategy for target impact performance
4.2. Parametric study across impact energies and development of design relationships
4.3. Experimental validation and discussion
5. Conclusion 43
